Posterior cruciate ligament (PCL) injuries are rare and infrequently occur in isolation. Although we have an increased knowledge of the anatomy and mechanism of injury, PCL reconstruction has not obtained the success of anterior cruciate ligament (ACL) reconstruction. In addition, frustrating to the surgeon is the lack of consensus regarding the optimal management of PCL injuries. Isolated PCL injuries (grades I and II) can be treated nonoperatively with protected weight-bearing and quadriceps muscle rehabilitation. However, some studies have demonstrated degenerative changes and poor objective outcomes associated with conservative treatment of PCL injuries.

The absolute indications for reconstruction of an isolated PCL tear would be for persistent instability (grade III) or a boney avulsion. However, some authors dispute the existence of an isolated PCL injury. Regardless, most PCL reconstructions occur in conjunction with a knee dislocation. Advances in the understanding of the anatomy and biomechanics of the PCL have led to an increased interest in arthroscopic reconstruction of the PCL. Anatomic studies have delineated separate characteristics of the anterolateral (AL) and posteromedial (PM) bundles within the PCL. The larger AL bundle has increased tension in flexion, whereas the PM bundle becomes more taut in extension. In addition, the smaller meniscofemoral ligaments also contribute to the overall strength of the PCL. The timing of PCL reconstruction is controversial, but an acute reconstruction is generally accepted for boney avulsion injuries or while addressing combined ligamentous injuries-especially a posterolateral corner injury. The double-bundle PCL reconstruction technique is most commonly performed in the chronic setting, when very little native ligament remains available for augmentation.

Contraindications to an acute PCL reconstruction would be in the setting of a traumatic knee arthrotomy or with a stiff knee. The double-bundle technique is not recommended if any bundle remains intact. In this scenario, we prefer a single-bundle augmentation, which is the most likely clinical presentation. We always attempt to preserve any remnant tissue whenever possible unless located directly at the insertion site of the target bundle. The grafts are passed around the meniscofemoral ligaments, which does increase the complexity of the reconstruction.

A thorough history and physical examination are obtained preoperatively in a clinic setting. It is important to determine the chronicity of the injury. Acutely, there is usually a history of a direct blow to the anterior lower leg or a hyperextension injury with concomitant mild swelling. A PCL injury may also occur in the setting of a knee dislocation with involvement of the posterolateral structures (approximately 60%). Chronically, instability may be the only complaint.

On physical examination, it is important to assess the neurovascular status of the injured limb. This is especially important if there is a history of a knee dislocation, which has a higher risk of such an injury. Inspect and palpate for an effusion followed by assessing the range of motion. With the knee in a flexed position, palpate for the natural tibial step-off and evaluate the anterior border of tibial plateau in relation to the femoral condyles. In addition, a Godfrey test can be performed whereby the lower leg is elevated with the knee flexed approximately 90 degrees to assess for the presence of a “sag.” A posterior drawer with the knee in 90 degrees of flexion is also performed to evaluate the amount of posterior tibial translation (Fig. 19-1). It is important to recognize the presence of a posterolateral corner knee injury, which will accentuate the posterior drawer. The gait pattern is inspected for any varus thrust. If a posterolateral corner injury is suspected, the physical examination should include a reverse pivot shift test, a dial test, a posterolateral drawer, and varus stress testing at both 30 and 90 degrees.

Radiographs of the knee should be performed to inspect for any fracture in the acute setting or for any medial or patellofemoral compartmental arthrosis in the chronic setting. Long-leg cassette films should be obtained if any coronal instability is suspected. Posterior tibial subluxation can possibly be seen on the lateral radiograph. Otherwise, a comparative stress lateral radiograph can also be obtained. A bone scan may be useful in chronic PCL insufficiency to identify degenerative changes. A magnetic resonance image (MRI) is essential not only to confirm a PCL injury, but more importantly to assess for any concomitant posterolateral corner injury or meniscal pathology that will affect the operative plan.